1. Field of the Invention
The present invention relates to methods and apparatus for removing smoke and gases from enclosed areas where fires are being fought, particularly apparatus mounted upon self-propelled fire-fighting vehicles.
2. Description of the Relevant Art
Ventilation techniques can be used in fire fighting to control the movement of air and smoke as well as hot, flammable or hazardous gases. Proper ventilation can serve many purposes. For example, with small fires, ventilation can exhaust smoke to minimize smoke damage to property. With larger, more serious fires, exhausting smoke can reduce the risk of personal injury to both firefighters and occupants of the burning structure. Proper ventilation can remove hot air and combustible gases, thus slowing the spread of the fire. Even in xe2x80x9cnon-firexe2x80x9d emergencies, ventilation can remove toxic and/or flammable gases arising from various sources.
Fighting and extinguishing fires in enclosed structures such as buildings often requires the firefighters to enter such areas to rescue occupants and/or to take more effective steps to fight the fire directly. However, the presence of smoke and gases in enclosed areas where fires are burning makes it very difficult for the firefighters to find their way inside, and breathing and protective apparatus must often be used, which limits the time such personnel can spend in actual firefighting. This is particularly difficult for xe2x80x9cblindxe2x80x9d fires, which may be defined as fires originating from sources that cannot be seen or located precisely, and which yield large quantities of smoke and gases. It would thus be desirable to evacuate or dissipate such smoke and gases from the area where firefighters are required to enter, to improve their effectiveness and provide for their safety while performing their duties. Furthermore, most fires burn upwardly in confined spaces, thus igniting and burning through the floors above. It is often necessary to send firefighters to the roofs of burning buildings to open spaces to ventilate the fire, thus creating personnel hazards. It would be desirable to reduce the tendency of the flames to move upward and avoid the necessity of roof ventilation.
A few patents can be found for apparatus designed to achieve these ends.
U.S. Pat. No. 2,120,563 discloses a fire truck mounting a compressor and other equipment designed to introduce compressed air into a confined space to expel smoke and gases, with the flow of air thereafter to be reversed to provide fresh air to the space.
L. C. Moore has at least three patents in this area of interest. His U.S. Pat. No. 1,874,573 discloses a portable fan and hood system which can be attached to a ground level window or other aperture of a burning building to withdraw smoke and gases. U.S. Pat. No. 1,926,298 discloses a fire truck carrying a blower and a long, flexible hose which can be introduced into a window or other opening in a burning building to withdraw smoke and gases. U.S. Pat. No. 2,078,580 discloses a similar fire truck carrying a power exhauster attached to an extensible smoke stack. Portable conduits can be attached to the smoke stack in sections.
Clark discloses a dual purpose fire fighting and ventilation apparatus in U.S. Pat. No. 4,986,364. The apparatus includes a rigid conduit which can be connected to a water source at one end and a nozzle at the other. The nozzle end is inserted into a window of a burning building and water is directed through the conduit and nozzle, which is directed to spray outwardly through the window. The result is an aspiration effect which draws smoke and gases out of the building. When enough smoke has been withdrawn, the nozzle can be repositioned and the flow of water redirected to attack the source of the fire directly.
Bateman and Panter disclose another fire fighting ventilation system in U.S. Pat. No. 4,886,233 which is a portable apparatus for supporting and operating ventilation fans. Wheels and adjustable legs and arms are provided to allow the fans to be positioned on uneven surfaces so as to evacuate smoke from accessible areas of burning buildings, preferably directing the flow out a window or the like.
Despite these early efforts, fire fighting is an evolutionary science, with efforts continuing to develop apparatus and methods to improve the effectiveness of fighting fires in various enclosed spaces. In some cases, modern construction materials and methods as well as the contents of various buildings have complicated the tasks of fire fighters. For example, many synthetic fabrics and construction materials used in modern buildings produce voluminous, dense smoke and toxic gases while burning. There is clearly a need for improved apparatus for evacuating smoke and gases from burning buildings and other enclosed spaces.
It is thus an object of the present invention to provide a mobile, self-propelled apparatus capable of removing smoke and gases from burning buildings or other enclosed spaces. Another object of the invention is to provide a self-propelled vehicle which can be positioned close to such burning buildings and provide a stable platform for apparatus to withdraw the smoke and gases. A related object of the invention is to provide a stable foundation for the apparatus when positioned close to a burning structure. A further object of the invention is to provide an extensible channel to penetrate the burning building and a powered exhaust system to remove the smoke and gases. Another object of the invention is to provide means for injecting fire extinguishing materials into the building once the smoke has been evacuated.
In accordance with the present invention, a mobile self-propelled evacuating fire vehicle is provided, comprising an extensible evacuation tube operatively connected to mechanical suction means and including means for positioning the tube for entry into a window or similar opening in a burning structure. Preferably, the evacuation tube can be extended and retracted by remotely-controlled power means to facilitate insertion into or withdrawal from such a window. The positioning means can include mechanical means for training the tube laterally, as with a rotary turret, and means for elevating and depressing the tube above and below the horizontal plane. The entry end or nose cone of the tube can be fitted with doors which can be opened and closed, again preferably by remotely-controlled power means. The entry end or nose cone can also be fitted with remotely-controlled power means for adjusting its aim in both lateral and vertical directions so as to aim the open doors in the most effective direction. This is particularly helpful when the tube is equipped with hoses or other channels to carry firefighting materials such as water or chemicals to the entry end of the tube and propel them toward the source of the fire. The vehicle should have sufficient wheels or other drive means to support each corner of the vehicle, and at least two drive wheels or other drive means. To facilitate movement through wet or slippery terrain, the vehicle should have all-wheel drive or the equivalent. Additionally, to facilitate providing a stable base for movement of the tube, the vehicle preferably has at least one wheel on each side which can be extended laterally and positioned vertically to support the vehicle, even on sloping or irregular terrain. The vehicle includes a prime mover for its own propulsion and power take-offs or auxiliary power units to meet all the energy needs involved in manipulating and exerting suction with the evacuation tube.
Additional objects and advantages of the present invention are described in, and will be apparent from, the following detailed description of preferred embodiments together with the drawings and appended claims.